Level 8

Total Experience Required 9,486

Level 100 progress: 0.14%

This is roughly the same as:

Killing 16 people in Warzone, or...
Killing 17 people in Execution, or...
Killing 14 people in Wingman, or...
Scoring 3,388 points in Guardian, or...
Scoring 10,311 points in Annex, or...
Scoring 6,241 points in Submission.

Horde (TU4)

Completing 24 waves on Casual, or...
Completing 16 waves on Normal, or...
Completing 12 waves on Hardcore, or...
Completing 10 waves on Insane.

Or a combination of the above. Have fun!